Water temp in Magnum (crate motor version). Where to place probe for gauge? Temp switch for fans?

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MRGTX

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Probably another noob question-- I have a probe for my water temp gauge and a switch for my electric fans.
One should go in the manifold...what about the other? Does it matter?

I'm not sure if it matters or not but the car is a Magnum 300 crate motor with LA style waterpump, etc. Mopar M2 manifold...

Thanks for any help and for not laughing at my endless ignorance. :D
 
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If all else fails, you can buy aftermarket spacers that go under the t stat outlet with tappins in them..........just a random one to illustrate

680-WN0028S.jpg
 
Exactly what I was thinking of. I have one from *I think* it says Joe's Performance. I'll edit this when I get home......
 
Probably another noob question-- I have a probe for my water temp gauge and a switch for my electric fans.
One should go in the manifold...what about the other? Does it matter?

I'm not sure if it matters or not but the car is a Magnum 300 crate motor with LA style waterpump, etc. Mopar M2 manifold...

Thanks for any help and for not laughing at my endless ignorance. :D

The hottest water travels out past the thermostat, through the radiator hose to the radiator's upper inlet. That adapter fits in an ideal place as long as you don't have a stuck thermostat.
 
Thanks to everyone.

I found this one. One review notes that it specifically does not fit the Manifold on his Magnum 360 despite seeing that it's compatible with Mopar small blocks. Is there anything unique about Magnum engines and their manifolds that I need to look for?

https://www.summitracing.com/parts/mez-wn0028s

The reviewer said that his manifold was an Edelbrock, fwiw.
 
Don't know unless it's the stat size which changed. I don't remember, I think the newer stats were smaller diameter? At leas one Ed I have is drilled for both stat patterns.........Like this

131542349266_1.jpg
 
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Thanks to everyone.

I found this one. One review notes that it specifically does not fit the Manifold on his Magnum 360 despite seeing that it's compatible with Mopar small blocks. Is there anything unique about Magnum engines and their manifolds that I need to look for?

https://www.summitracing.com/parts/mez-wn0028s

The reviewer said that his manifold was an Edelbrock, fwiw.

I don't know off the top of my head, but I can snap some pics of my Magnum EFI Airgap if you need them.

Also, grab one of those hand-held laser temperature guns from Harbor Freight or EBay. They really come in handy for learning what's what as far as normal temps are on your motor.
 
Quick question to follow up on this- using the part suggested above that extends the thermostat housing, the thermostat interferes with the temp probes (gauge and fan sensor)...is there an optional thermostat design that is shorter in the vertical dimension?

How much damage might I do for driving around with no thermostat in the meantime? It does eventually get up to operating temps.
 
Can you post a pic of the temp unit sender please?

No damage... don’t drive it until it knocks or steam escapes.
 
Can you post a pic of the temp unit sender please?

No damage... don’t drive it until it knocks or steam escapes.

I thought everyone waited for the steam and the knocking before doing 0-100 pulls! :D

I'll see if I can find a pic of the probe. Basically, it's a ~1" long, ~3/8" diameter cylinder connected to a capillary tube. Not sure if that helps...
 
FUNNY!!!! In a slow moment my super and I were just discussing yesterday how "unhandy" it was that Ma did not make it easy to install mechanical temp gauges!!!! Too bad Mopar did not go to a head mounted setup like Chev. that is lower in the coolant, and if you get a leak, won't leave the sensor "high and dry"
 
Did anyone give this a shot and how did it turn out? This seems like the simplest way to have a mechanical temp gauge. All the ports I found on the m1 were too small for the fitting.
 
Mine has an aftermarket temp gauge in an aluminum piece that you cut the top radiator hose in half and install. Don’t really like the looks of it all that much but it works good.
 
This will fit the standard early thermostat housing. You’ll have to poke around for a smaller one.

image.jpg
 
Some brands of gauges have adapters available (the gauge fitting is proprietary) that bush down to 3/8 pipe, and I remember one with a small sensor probe that went clear down to 1/4" piple. This was an import, years ago
 
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